I. Field of the Invention
The present invention provides a method for removing decay and/or carious lesions from teeth and especially from human teeth.
II. Description of the Prior Art
Carious lesions or tooth decay is initiated by bacteria which reside in tooth plaque. These bacteria produce acids which diffuse through a matrix of water-protein-lipid and attack the hydroxyapatite crystals which form the tooth enamel.
These acids ultimately dissolve the hydroxyapatite crystals which form the tooth enamel and invade the tooth dentin. At that time the tooth requires restoration, and such restoration is typically accomplished by drilling the decay from the tooth and thereafter filling the tooth. Since the tooth decay diffuses under the enamel and into the dentin, a portion of the enamel around the point of penetration usually must also be removed during the drilling process.
There have been a number of previously known experiments in which teeth have been subjected to laser irradiation to determine the alteration, if any, of the physical and/or chemical properties of the dental enamel. These studies have shown that the hydroxyapatite crystals that form the enamel fuse somewhat at the surface when lased and renders the enamel more impervious to acids of the type which cause tooth decay. These previous studies, however, have also concluded that the use of a laser cannot be used to remove tooth decay since the power level necessary for the laser to burn through the enamel also significantly heats the tooth and can kill the tooth nerve. For this reason, lasers have not been previously used to remove tooth decay.